Fritz samuel syelssos



(No Model.)

I F, S. SVENSON GOMPASSES. No. 295.076;

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UNITET) Turns FRlTZ SAMUEL svnnson, or LUND, sulinn,

ATENT @rrren,

swnnnn.

COMPASSES.

SPECIFICATION forming part of Letters Patent No. 295,076, dated MarchApplication filed October HI, 1853. (No model) Patented in Sweden July3, 1883, No. 237.

To all whom it may concern I Be it know u that I, FRITZ SAMUEL Svnnson,

. a subject of the King of Sweden, and a resident of Lund, in theProvince of Shane and Kingdom of Sweden, have invented certain newanduseful Improvements in Compasses;

and I do hereby declare that the following is full, clear, and exactdescription of theinvention, which will-enable others skilled" in theart to which it appertains to make and use the same, reference being hadto the accompanying drawin s, which form a partof this specification,and in which- -Figure 1 is a side view of my improved compasses andruler for blaclzhoarddrawing and similar drawing, and Fig. 2 is alongitudinal vertical section of the same.

Similar letters of reference indicate corresponding parts inboth thefigures.

My invention has relation to rulersaud compassesforblackboardand similardrawing; and it oonsistsin the detailed construction and combination ofparts of the same, as hereinafter more fully described and claimed.

In the accompanying drawings, the letter A indicates a flat graduatedruler, havingits upper edgeprovided with a metallic strip, B, and havinga block, 0, fastened to one end at a right angle to the ruler. Thisblock is thicker than the ruler, and its sides project equally to bothsides of the same, so that the block will serve the same purpose for theruler as the head of a T-square. The lower end of the block is split atDin a plane at a right angle to the plane of the ruler,,and the said endis inclosed in a metallic frame or open cap, E, secured to the outersplit half, F, of the lower end of the block, and slightly larger thanthe end of the block, allowing the two split jaws or halves of the blockto open or close, and a set-sorewpG, turns in a threaded aperture, H, inthe inner side of the frame, bearing with its end against the innerhalf, I, of the split end of the block.

The block has a longitudinal bore, J, opening at the lower split end ofthe same, one-half of the bore being in each jaw or half, and the saidhere or recess serves for the reception of the chalk, crayon, or otherdrawing material used, the clamping-jaws allowing the same to beadjusted between them. A block, K, of the same thickness as the rigidblock C,slidcs with a lon gitudinal slot, L, in its upper end, upon theruler, and has a metallic cap, M, at its upper end, having a femalethreaded perforation, N, which perforation extends through the upper endof the block, and a set-screw, 0, turns in this perforation, and has asleeve, P, upon the portion above the cap and below the head of thescrew,which forms a handle turning upon the stem of the screw. The lowerend of the screw bears against a plate, Q, having its ends turned up oneach side of the block, fitting in the upper end of the slot, bearingwith its uppersurface against the upper end of the same, and bearingwith its lower surface against the upper edge of the ruler, the platesliding in the upper end of the slot guided by the upturned ends andserving to clamp the ruler in the slot when the setscrew is screweddown. The lower end of the block K is reduced at R,forn1- ing shouldersS, and a sharp-pointed pin or needle, T, is secured in the end of thereduced portion. which portion is incasedina metallic sleeve, U, havingaflange, V, at its upper end,

which fits against the shoulders, while its lower end is reduced,forming a narrowerzsleeve,W, having screwihreads upon its inner side,into which sleeve a rubber block, X, fitting upon the end of the needle,fits and turns, having corresponding threads upon its upper end.

When the device is used as a pair of compasses, the needle is placed atthe point where the center is to be, and the rubber block, bearing uponthe sides of the center against the surface of the blackboarchwill serveto steady the point of the needle, prevent the same from passesconsisting of a bar or rod having a rigid 9 block and a sliding block ortwo sliding blocks, one provided with a crayon or piece of chalk, andthe other provided with a point; andI do not wish to claim suchconstruction, broadly; but

WVhat I claim, and desire to secure by Letters Patent of the UnitedStates, is-

1. In compasses for use in blackboard or similar drawing, thecombination of a sharp metallic point at the end of one of the legs, and

a rubber block slipped over the point, the latter penetrating the block,covering the entire point or needle, excepting the extreme point, as andfor the purpose shown and set forth.

2. The combination of the ruler having the crayon-holding block at oneend,a slotted block sliding adjustably upon the ruler, and having aneedle at its lower. end, and a rubber'block slipped upon the needle,the latter penetrating the block and covering the entire needle,excepting the point, as and for the purpose shown and set forth.

In testimony that I claim the foregoing as my own I have hereuntoaffixed my signature in presence of two witnesses.

' FRITZ SAMUEL SVENSON.

' Vitnesses: Enw. LUNDQVIST MATMI, F. N. NYBERG.

